Generally, there are known a hose formed by vulcanizing in a state in which a resin covers an outer surface and the resin being removed after vulcanization, and a hose formed by vulcanizing in a state in which a cloth member wraps spirally an outer surface, and the cloth member being removed after vulcanization.
In addition, there is known a method for inspecting appearance of a long-length object which includes the steps of using, for example, an image taking device which can take images of an outer surface of a long-length hose continuously, taking images of an outer surface of a long-length hose continuously with the image taking when the long-length hose is moving in a length direction, and judging existence of unevenness, a defect, and the like on an outer surface of the hose on taken images.    Patent Document 1: Japanese Patent publication H10-264174    Patent Document 2: Japanese Patent publication 2007-003243